A connector interface of a terminal is a critical component of overall system design, since the interface connector can be utilized for transmitting data between a host of accessories, and can also act as a power conduit for providing power to, for example, a battery-powered device during charging of an on-board battery.
When exposed to rugged and dirty environments, the connector interface system is often a weakest link in maintaining power and signals to the device. For example, routine use of a portable or handheld device that operates in a base station configuration often requires removal from and replacement (e.g., a cycle) into the base station or charging unit when not in use and/or when charging is needed. Such systems can experience high cycle applications where the device is removed and replaced significantly over the device's lifetime.
A connector interface system of a device/station pair typically includes two mating connectors, e.g., one connector on the device and its mating connector in the station. Each connector comprises one or more plated contacts that when utilized on the device that is repeatedly cycled with the base station, the contacts exhibit a wearing-away of the contact plating. The plating wear is a common problem in a conventional system that is usually caused by the repeated wiping action of the pin (or male) contact against the socket (or female) contact. In industrial applications where the interface connectors will be mated and unmated in excess of 100,000 times, particularly in transportation and logistics, contact wear is a major problem operating to degrade the connection and overall usefulness of the device.
Referring initially to the drawings, FIG. 1 illustrates an isometric of a conventional connector pair assembly 100 that utilizes the wiping form of contact. A female connector assembly 102 is designed for compatible interface to a male connector assembly 104. The female connector 102 includes a number of female contacts 106 that come into operative contact with respective male contacts 108 of the male connector 104 when the connectors 102 and 104 are engaged. The male contact 108 includes a bend feature 110 that is designed to enter into (and out of) contact with its respective female contact 106 by sliding along the corresponding female contact 106 when the connectors 102 and 104 are engaged (and disengaged). Thus the bend feature 110 coming into contact with the respective female contact during engagement and disengagement of the connectors 102 and 104 forms the wiping action on the metals of the two contacts 106 and 108 that in high cycle applications eventually wears away the contact plating on the surface on either or both of the contacts 106 and 108.
Referring now to FIG. 2, there is illustrated a side view of the conventional connector pair of FIG. 1 incorporating the wiping style of contact. The male connector 104 includes the male contact 108 with the bend feature 110, and further, a contact lug 200 for permanently connecting a suitable wire thereto. The female connector 102 includes the corresponding female contact 106 integrated therein such that when the connectors 102 and 104 are brought into engagement, an upper surface 112 of the bend feature 110 slidably engages a lower surface 202 of the female contact 106 for a short distance along the length of the female contact 106 to facilitate an electrical connection. This wiping action causes metal plating wear during the engagement process. Of course, contact wear also occurs in the reverse operation, since the contacts move along one another when the connectors 102 and 104 are disengaged. The wear associated with such wiping action contact design can be greatly reduced or even eliminated if a tip-to-tip contact design was implemented. Note that the illustrations of FIG. 1 and FIG. 2 are not necessarily to scale, or to a particular design, but are intended to simply show the general features of the wiping form of contacts in a conventional connector pair.
Alignment of the male and female connectors is also a common problem, particularly in pin-in-socket type connectors. Because of the intolerant stack-up associated with the terminal assembly and connector itself, compounded with a similar stack-up on the accessory side, alignment of the connector halves can be a serious issue. Pin-in-socket type connectors have the most significant alignment issue; if the pins and sockets are not accurately lined up, pins can be bent and/or broken off as the user attempts to force the two mating connector halves together.
Referring now to FIG. 3, there is illustrated an isometric of a conventional pin-in-socket type of connector assembly. A male connector assembly 300 is manufactured with one or more pin contacts 302, and a compatible female connector assembly 304 includes one or more corresponding socket contacts 306. When the connectors 300 and 304 are moved into engagement, the pin contacts 302 slide into respective socket contacts 306 to facilitate an electrical connection. However, misalignment of any pin contact 302 to any socket contact 306 can cause the user to twist or struggle with the connectors 300 and 304 in an attempt to align all of the pins to the respective sockets for full engagement of the connectors 300 and 304. Such a system not only is susceptible to the alignment problem, but also contends with the contact plating wear problem associated with the wiping form of contact.
Referring now to FIG. 4, there is illustrated a side view of the conventional connector pair of FIG. 3 that incorporates the pin-in-socket style of contacts. The male connector 300 includes the plated pin contact 302, which pin contact 302 includes a pin head portion 400 that slides into a corresponding plated socket slot 402 of the socket contact 306 of the female connector 304. This design is also burdened with wear of the contact plating on a surface 404 of the pin head portion 400 that comes into contact with an inside surface(s) 406 of the socket slot 402, since the wiping action is present between the pin head portion 400 and the inside surface(s) 406. Of course, the inside surface(s) 406 of the socket slot 402 also exhibit plating wear in high cycle applications, which reduces the lifetime of the device in which such contact style is used.
Alignment becomes even more of an issue with the pin-in-socket style of contacts, since repeated use in high cycle applications can cause one or more pins to bend out of alignment with the respective female socket 402. Furthermore, connector housing wear can be a factor in misalignment of the pins to the sockets. Still further, the more contacts in the connector assembly, the more difficult it is to ensure that all contacts are properly aligned to make the electrical connection. The wear associated with such wiping action, and alignment issues with the pin-in-socket contact design can be greatly reduced or even eliminated if a tip-to-tip contact design was implemented.
What is needed is a more reliable interface connector system for use in high cycle applications that utilizes a contact interface design that minimizes contact wear and alignment issues.